Differences in protective factors of substance use in early and middle adolescence

This study focuses on possible differences in protective factors of substance use in early and middle adolescence. These possible differences are analysed by means of the same structural equation model applied to two different samples of adolescents: the first sample is made up of 450 adolescents, ages 12 to 14 years, and second of 203 adolescents, ages 15 to 17 years. The results indicate that adequate family communication is a protective factor in both samples, whereas high social self-esteem is proposed as a risk factor in middle adolescence. The adolescent's family self-esteem and attitudes towards authority are also relevant factors in both samples. These results may have important implications in the development of future intervention programmes.     

AIDS‐NGOs and political participation: Brazilian and Canadian experiences

Non‐governmental organizations (AIDS‐NGO) are an instrument of political pressure and assistance, often serving as a life reconstruction aid for people living with HIV/AIDS. In this case study, we analyze data from historical documents, in‐depth interviews, and questionnaires obtained from participants and community agents in two AIDS‐NGOs: one in Canada (NGO‐Ca), and another in Brazil (NGO‐Br). Despite contextual differences, both NGOs are involved in a fight against stigma and discrimination that may aggravate existing social exclusion. Variances in political participation are nevertheless evident. In NGO‐Ca, efforts are directed towards maintaining and consolidating human and social rights. In NGO‐Br, the primary goal is building these. In NGO‐Ca, the participant is part of a structured organization where he or she receives the required supports; the NGO is thus a service provider. Conversely, in NGO‐Br, the participant is both the actor and author of collectively constructed supportive actions. It is hoped that the lessons learned from this limited case study will assist in the strengthening of AIDS‐NGO organization and activity, particularly in the developing world context. Copyright © 2008 John Wiley & Sons, Ltd.     

Paradoxical sleep deprivation impairs acquisition, consolidation, and retrieval of a discriminative avoidance task in rats

The aim of the present study was to investigate the effects of paradoxical sleep deprivation (PSD) for 96 h on the learning/memory processes in rats submitted to the plus-maze discriminative avoidance task (PM-DAT), which simultaneously evaluates learning, memory, anxiety and motor function. Four experiments were performed in which rats were submitted to: (1) post-training and pre-test PSD; (2) post-training or pre-test PSD; (3) pre-training PSD or pre-training paradoxical sleep (PS) rebound (24 h) and (4) pre-test PSD rebound. Concerning Experiment I, post-training and pre-test PSD induced memory deficits, an anxiolytic-like behavior and an increase in locomotor activity. In Experiment II, both post-training PS-deprived and pre-test PS-deprived groups showed memory deficits per se. However, only the pre-test PS-deprived animals presented anxiolytic-like behavior and increased locomotor activity. In Experiment III, pre-training PS-deprived rats showed learning and memory deficits, anxiolytic-like behavior and increased locomotor activity. A 24h-sleep recovery period after the PSD abolished the learning and memory deficits but not anxiety and locomotor alterations. Finally, sleep rebound did not modify acquisition (Experiment III) and retrieval (Experiment IV). This study strengthened the critical role of paradoxical sleep (but not sleep rebound) in all the phases of learning and memory formation. In addition, it suggests that PSD effects on acquisition and consolidation do not seem to be related to other behavioral alterations induced by this procedure.     

Role reversal changes during the ontogeny of play fighting in male rats: Attack vs. defense

From weaning until sexual maturity, the rates at which young male rats hold each other supine during play fighting appear to become progressively asymmetrical. These changes have been previously thought to reflect an initial lack of dominance and a later development of dominance-subordinance relationships. In this paper it is shown that pairs of male rats exhibit asymmetries in playful attack and playful defense throughout development. The changes, resulting in greater asymmetry of pinning rates, are shown to result from age-dependent changes in defensive tactics; the relationship, therefore, remains constant while the form of the behavior changes. Furthermore, it is not the animals showing the highest rates of playful attack who become dominant in older ages.     

Targets and tactics of agonistic and precopulatory behavior in montane and prairie voles: Their relationship to juvenile play-fighting

Play-fighting by juvenile montane and prairie voles involves attack and defense of the head, neck and shoulders. Since during play animals typically borrow behavior patterns from other functional contexts, two adult behavioral contexts were compared to juvenile play-fighting. These were serious fighting and sexual encounters. During serious fighting in a resident-intruder paradigm, most bites are directed at the rump and lower flanks. During sexual encounters, especially in precopulatory behavior, the head, neck and shoulders are gently contacted. Therefore, play-fighting by juveniles would appear to involve attack and defense of areas of the body contacted in adult precopulatory behavior, not adult fighting. Furthermore, the species-specific differences in juvenile play-fighting were also found to be matched by species-specific differences in precopulatory behavior. In both playful and precopulatory encounters, montane voles contacted the head and used upright defensive behaviors more often than prairie voles. In contrast, prairie voles made mutual contact more often and were more likely to rotate to supine in defense of contact to the nape and head. These findings support our hypothesis that juvenile play-fighting in muroid rodents involves the precocial expression of precopulatory, not agonistic behavior.     

Polydrug use trajectories and differences in impulsivity among adolescentsTrayectorias de policonsumo y diferencias en impulsividad entre adolescentes

Background/Objective: Although alcohol, tobacco and cannabis are the most widely consumed drugs, sparse data exist regarding polydrug use in adolescents and its relationship with impulsivity. This study aims to identify trajectories of polydrug use and analyze differences in impulsivity between them. Method: A total of 1,565 adolescents (54.4% males; mean age = 13.02, SD = 0.57) were annually assessed over three years using the Barratt Impulsiveness Scale, the Zuckerman Impulsive Sensation Seeking Scale, a Stroop Test and a Delay Discounting Task. Frequency of alcohol, tobacco, and cannabis use, intoxication episodes and problem drinking were also assessed. Polydrug trajectories were identified using latent class mixed modelling. To examine differences in self-reported and behavioral impulsivity two mixed multivariate analyses of covariance were used. Results: Three trajectories of substance use were found. The ‘Experimental use’ and the ‘Early use’ trajectories presented the lowest and highest impulsivity, respectively. Substance use increases in the ‘Telescoped used’ trajectory were associated with parallel increases in impulsivity. Conclusions: individuals with divergent patterns of substance use during adolescence differ in their impulsiveness, primarily in general impulsivity and sensation seeking. Present findings suggest the relevance of these facets as possible targets for interventions preventing the onset and escalation of substance use.     

Estimating Creativity with a Multiple-Measurement Approach Within Scientific and Artistic Domains

This article presents the structure and the composition of a newly developed multifaceted test battery for the measurement of creativity within scientific and artistic domains. By integrating existing procedures for the evaluation of creativity, the new battery promises to become a comprehensive assessment of creativity, encompassing both domain-general and domain-specific components. In particular, the test battery was designed for the measurement of the 2 main stages of the creative thinking process: ideation and evaluation. The test battery also includes 2 measures of creative achievement and can be used to assess professional levels of creativity in artistic and scientific creativity, as well as everyday creativity. Because creative thinking is not an isolated phenomenon in human behavior, the battery includes the measurement of 2 constructs, intelligence and personality, both of which are highly relevant for creativity. Preliminary results from a vast administration campaign of this test battery are presented.     

Agonistic versus amicable targets of attack and defense: Consequences for the origin,function, and descriptive classification of play-fighting

Play-fighting appears to involve the behavior patterns of attack and defense otherwise seen in serious fighting. The degree of similarity, however, depends on the body targets attacked and defended during these forms of fighting. For many taxa, including diverse mammalian families and some birds, the same targets are attacked and defended during both play-fighting and serious fighting. However, for several species of muroid rodents, the targets of play-fighting are not the same as those of serious fighting. In these cases, the tactics of attack and defense are also different. It is argued that for these muroid species the playful targets have arisen from amicable behavior (e.g., social investigation, greeting, allogrooming) rather than, as appears to be the case in so many other taxa, from agonistic behavior. These data strongly suggest that “play-fighting” has evolved from different precursors in different taxa and thus has multiple origins. Furthermore, these data have an important bearing on the universal applicability of many of the suggested functions of play-fighting and also on how such behavior is to be described and classified.